One of the most interesting model loader for Java 3D is the Never Winter Nights Model loader from Arthur Biesiadowsk.
This loader is for animated characthers NWM game (MDL ). You can find a lot of NWN models in the Internet.
The oficial web site is here.
It was broke for last versions of Java3D, but I fix it and made it available in the link below.
It includes a Viewer and some models from BioWare ( http://nwn.bioware.com/downloads/viewer.html )